Your best bet would be to tune in Meigs ATIS and see what it says. I would imagine if the one runway is closed then the tower is still closed. But I do not know if they have closed the helipads or not, so the tower may still be open for those...

I'd like to make an interesting observation about the downtown Chicago TFR (Temporary Flight Restriction). If you look at the graphic, you'll see the area this TFR affects. The interesting thing is that this TFR is only prohibiting flights below 3000ft AGL in this area. Well, I wouldn't want to operate below 2800ft AGL anyway in this area to provide clearance in accordance with Part 91. This TFR is totally unnecessary because law abiding pilots aren't a threat, and a terrorist won't be stopped by it anyway.

Text of the TFR
3/2290 IL.. FLIGHT RESTRICTION CHICAGO, IL. EFFECTIVE 0303221700 UTC UNTIL FURTHER NOTICE, PURSUANT TO 14 CFR SECTION 99.7, SPECIAL SECURITY INSTRUCTIONS, EXCEPT FOR MEDEVAC, LAW ENFORCEMENT, RESCUE/RECOVERY, EMERGENCY EVACUATION AND FIRE FIGHTING OPERATIONS, ALL VFR FLIGHT OPERATIONS ARE PROHIBITED WITHIN AN AREA BEGINNING ON THE LAKE MICHIGAN SHORE LINE (415232N/873658W OR THE CHICAGO O'HARE /ORD/ VOR/DME 115.4 DEGREE RADIAL/14.6 DME), THEN WEST VIA THE EISENHOWER EXPRESSWAY TO THE INTERSECTION OF THE DAN RYAN EXPRESSWAY (415232N/873844W OR THE ORD 118 DEGREE RADIAL AT 13.4 DME) THEN NORTH VIA THE DAN RYAN/KENNEDY TO THE INTERSECTION OF ASHLAND AVENUE (415454N/874004W ORORD 110.2 DEGREE RADIAL AT 11.5 DME) THEN NORTH VIA ASHLAND TO THE INTERSECTION OF IRVING PARK ROAD (415716N/874010W ORORD 098.6 DEGREE RADIAL AT 10.7 DME) THEN EAST VIA IRVING PARK TO LAKE MICHIGAN SHORELINE (415718/873828W ORORD 097.4 DEGREE RADIAL AT 12 DME) THEN SOUTH VIA THE SHORELINE EXCLUDING OLIVE PARK AND NAVY PIER TO THE POINT OF BEGINNING AT AND BELOW 3000 FEET AGL UNLESS AUTHORIZED BY ATC. JEFF ULLOM, (847) 608-5618, IS THE POINT OF CONTACT. ELGIN TRACON, (847) 304-9368, IS THE FAA COORDINATION FACILITY. WIE UNTIL UFN